1. Field of the Invention
The present invention generally relates to a plug connector used for balanced transmission, and particularly relates to a plug connector provided with substantially right-angled contact portions protruded backward from the housing.
2. Description of the Related Art
Recently, along with rapid improvement in personal computers and computer networks, there is a need for transmitting a large amount of data, particularly moving-image data. In order to transmit a large amount of moving-image data, a high-speed transmission of at least 1 gigabit/sec is required. However, an unbalanced transmission system is not suitable for such a high-speed transmission since it is easily affected by noise. Thus, for a high-speed transmission, a balanced transmission system is preferred since it is less affected by noise as compared to the unbalanced transmission system.
Plug connectors can be roughly divided into straight-type plug connectors and right-angled type plug connectors. A straight-type plug connector is provided with contact elements protruded vertically downward from the housing. A right-angled type plug connector is provided with substantially right-angled or L-shaped contact elements protruding backward from the housing and bent vertically downward. Since lengths of the contact elements are longer for the right-angled contact elements, there is a higher possibility of requiring an impedance matching for the right-angled type plug connectors.
Therefore, there is a need for a plug connector which can be used in a balanced transmission system and which has a structure taking into account an impedance matching of signal contacts.
In the related art, a right-angled type plug connector taking in account an impedance matching is known, which plug connector is provided with a bracket made of electrically insulating synthetic resin covering the substantially right-angled contact elements protruding backward from the housing.
However, with the plug connector of the related art, since the bracket is provided beneath the contact elements, upper sides of the contact elements are completely exposed to the air. Therefore, an impedance matching is not sufficiently implemented by changing a material used as the synthetic resin of the bracket.
Therefore, there is a need for a plug connector having substantially right-angled contact elements and used for balanced transmission, which plug connector can easily implement an impedance matching.